Interplay of accelerated biological aging, lifestyle factors, and genetic susceptibility in cognitive function: a...

Cognitive impairment is a significant health concern in aging populations, but the interplay between biological aging, lifestyle factors, and genetic susceptibility remains unclear. This study examined whether accelerated biological aging is associated with cognitive impairment, whether lifestyle modifies this association, and how genetic background influences these relationships in Chinese older adults. In this cross-sectional study (2022-2023), 7033 participants from southwestern China were included. Accelerated biological aging was calculated as the residual difference between biological age (based on 10 biomarkers) and chronological age. Lifestyle was assessed via a composite index (smoking, alcohol, physical activity, diet, sleep). Cognitive function was measured using the Chinese Mini-Mental State Examination (C-MMSE), and genetic risk was evaluated through polygenic scores and APOE ε4 status. Linear and logistic regression models assessed associations between accelerated aging and cognition. Accelerated biological aging was associated with lower MMSE scores ( β = -0.243, 95% CI: -0.354, -0.133) and higher cognitive impairment prevalence (OR = 1.098, 95% CI: 1.040, 1.158). An unhealthy lifestyle exacerbated cognitive impairment in biologically older individuals (RERI = 0.25). Those with both accelerated aging and unhealthy lifestyle had the lowest MMSE scores ( β = -1.424, 95% CI: -1.846, -1.003) and highest odds of cognitive impairment (OR = 1.467, 95% CI: 1.194, 1.803). These effects were consistent across all genetic background subgroups. Accelerated aging was associated with lower cognitive function, especially in individuals with unhealthy lifestyles, regardless of genetic susceptibility. This highlights lifestyle modification as a potential intervention target for aging-related cognitive impairment.